Apparatus to restore heartbeat



Jan.. 1.3,- 1970 w. J. MULLIKIN 3,489,140

' APPARATUS T REsToR'E HEARTBEA'T' Filed Aug. 5, 1960 3 Sheets-Sheet l 1N VENTOR Wilbur J. Mul/Min BY Mmmm ATTORNEY Jan. 13, 1970 w. J. MULLIKIN APPARATUS TO RESTORE HEARTBEAT 5 Sheets-Sheet 2 Filed Aug.

INVENTOR Wilbur J Mu//k/'n SMM@ ATTORNEY w. J. MULLIKIN 3,489,140

APPARATUS TO RESTORE .HEARTBEAT Jan. 13, 1970 Filed Aug. i,

3 Sheets-Sheet 3 I N VEN TOR Wilbur Mul/Min BY WM ATTORNEY United States Patent O M 3,489,140 APPARATUS T RESTORE HEARTBEAT Wilbur J. Mullikin, Washington, D.C., assigner to Hyman Hurvitz, Washington, D.C. Filed Aug. 5, 1960, Ser. No. 47,717 Int. Cl. A61h 7/00 U.S. Cl. 128--51 4 Claims This invention relates generally to a surgical appliance and more particularly to apparatus for mechanically applying rhythmic pressure to a patients chest in order t0 restore heartbeat Without the use of surgery.

A manual technique for restoring heartbeat has proved to be successful and is accomplished by the person utilizing the procedure placing one hand over the other with the heel of the lower hand resting on the lower part of the patients breastbone. Then rm downward pressure is applied about once a second to push the breastbone inward about an inch toward the spine.

At the end of each stroke the hands are lifted to allow full expansion of the chest. It has been found that this procedure can be continued for a substantial period without harm to the chest or heart.

The technique mentioned above has been proved and sets up an artificial pumping action which forces blood out of the ventricles, the two lower chambers of the human heart. The procedure is continued until the heart starts beating and resumes its own pumping or it is evident that the heartbeat cannot be restarted.

The human element plays a big part in the application of the aforementioned technique. One major problem is to apply the right amount of pressure, since too much pressure has actually resulted in rib breakage, and further to apply the pressure in a rhythm most closely conforming to the actual heartbeat.

Further, since the application of this heartbeat restoration procedure may extend to a period of an hour or more, the operator may get tired with the accompanying result of undesirable lack of rhythm in pressure application, misplacement of the hands in addition to the normal physical discomfort which results.

A primary object of this invention is to provide mechanical apparatus to uniformly and accurately accomplish the heart restoration system heretofor thought only possible through manual technique.

A further object of the invention is to provide apparatus of the character mentioned which is adjustable to patients of diiferent physiques.

Another object of this invention in conformance with that set forth is to provide apparatus of the character set forth which may be readily and expeditiously orienteld and applied to a patient to be treated.

A still further object of the invention is to provide apparatus of the character mentioned which is portable and may be manually operated in the event of a failure of the power source for the apparatus.

And yet another object of the invention is to provide apparatus of the character mentioned which mechanically performs a heart restoration procedure of the character mentioned with the degree of accuracy and uniformity required to restore the heartbeat with a minimum expenditure of physical effort on the part of an operator without requiring extensive experience and practice by the operator.

The foregoing statements are indicative in a general way of the nature of the invention. Other and more specie objects and the nature and advantages of the instant invention will be apparent to those skilled in the art upon a full understanding of the construction and operation of the device.

3,489,140 Patented Jan. 13, 1970 ICC Several embodiments of the invention are presented herein for the purpose of illustration, and it will be appreciated that the invention is susceptible to incorporation in other rnodications coming equally within the scope of the appended claims.

In the drawings:

FIGURE 1 is an elevational view of one embodiment of the invention shown in relation to a patient disposed on a support table, portions being broken away and shown in section for purposes of clarity, and showing in phantom lines a removable handle facilitating optional manual operation of the apparatus;

FIGURE 2 is a fragmentary side elevational view looking from right to left at FIGURE 1;

FIGURE 3 is an enlarged fragmentary elevation of a portion of FIGURE 1 taken substantially at the plane of line 3-3 on FIGURE l, showing a portion of the power operating mechanism of this embodiment;

FIGURE 4 is an enlarged fragmentary section taken substantially on the plane of line 4 4 of FIGURE 1, showing a detail of the adjustable supports for the apparatus;

FIGURE 5 is an enlarged fragmentary elevation taken substantially on the plane of line 5 5 of FIGURE 1 with portions broken away to show another adjustable detail of the apparatus support;

FIGURE 6 is a fragmentary elevation of an operating screw similar to that shown in FIGURES 1 and 3 to illustrate how variations of the speed of the pressure applying member may be obtained;

FIGURE 7 is a fragmentary view of another embodiment of power operated means for the apparatus;

FIGURE 8 is a side elevational view looking from right to left at FIGURE 7;

FIGURE 9 is a view similar to that of FIGURE 7, showing how diierences in speed of travel may be obtained when the pressure applying changes in direction;

FIGURE l0 is a view similar to that of FIGURE 1, on a reduced scale, showing an embodiment of a manually operated apparatus incorporating the principles of the invention;

FIGURE 1l is a sectional view taken substantially on line 11-11 of FIGURE l0 with portions broken away to show structural details;

FIGURE 12 is a view similar to that 0f FIGURE 1l, showing still another manually operated embodiment of the invention in which a greater mechanical advantage is utilized;

FIGURE 13 is a top plan View of the embodiment of FIGURE l2, illustrating the manner in which the apparatus may be anchored beneath the patient being treated; and

FIGURE 14 is a still further embodiment of the invention in which the apparatus is strapped onto the patient being treated.

Referring to the drawings in detail, particularly to FIGURES 1-5, a bed is indicated at 10 and has a patient P disposed face-up thereon. Although this embodiment of the invention shows means whereby the apparatus may 'be mounted on a =bed or the like, it will subsequently become apparent that a patient requiring treatment of the character involved may be treated in the field, i.e. at the site of a re, swimming pool, carbon monoxide filled garage, etc., and thus the bed is shown by way of illustration and not limitation.

The bed includes horizontal side rails 12 on either side of the patient P to which are anchored, as will be described, the novel apparatus 14 for externally manipulating the patient's heart and simulating a pumping action therein to promote reactivation or beating of the organ.

The apparatus 14 comprises support means indicated generally at 16 anchored in operative relation to the patient P and upon which is mounted force transmitting means indicated generally at 18 for operating heartmanipulating means indicated generally at 20.

The support means 16 comprises an adjustable, generally inverted U-shaped frame 22 which will be accommodated over beds of different widths and patients having different physiques. The frame 22 includes vertically adjustable legs 24 which comprise telescoped upper and lower sections 26 and 28, respectively; see FIGURES 1, 2 and 4. The upper section is terminally slotted longitudinally at 30 and is longitudinally tapered and threaded at 32 at the portion 30 and receives thereon an internally tapered, threaded clamp nut 34. The nuts 34 may be back off to adjust the frame 22 with respect to the height of the chest C of the patient being treated.

The upper leg sections 26 include an integral, transverse block element 36 which is transversely apertured at 38. The frame 22 includes a transverse channel element 40 which is open at opposite ends and includes a top web 42, side flanges 44 and inwardly turned, lower, spaced lip portions 46. The flanges 44 include aligned transversely spaced apertures 48 above the lips 46 and spaced therealong, and the block elements 36 have a cross section conforming to the inner surfaces of the channel element 40 at the lips. The apertures 38 of the block elements are alignable with a pair of opposed apertures 48 of the channel elements, one of which being internally threaded for removably receiving a screw 50 therethrough. Thus the width of the frame 22 may be readily adjusted and may be readily dismantled for purposes of storage and ready portability.

The lower leg section 28 includes a lower rotatable portion 52 which includes an axial shaft portion 54; see FIGURE 5, which is diametrically apertured at 56. The leg section 28 has secured by a rivet 58, or the like, a .l-shaped spring latch 60 including an inwardly projecting pin portion 62 displacably extendable through a transverse aperture 64 in the leg section 28. The shaft portion 54 forms with the leg section portion 52 a bearing shoulder 66 which will orient opposite ends of the aperture 56 to lockingly receive the terminal end of the pin portion 62 therein. This expedient will permit 180 degrees of oriented rotation of the portion 52 for a purpose to become apparent, however, it is possible to rotate the entire leg section 28 about its longitudinal axis in the manner illustrated, for example, in FIGURE 13. The separate section 52 will permit rotation of anchoring feet, to be described, beneath the body of a patient or permit the operator of the apparatus to place his feet thereon as will subsequently be described in detail. Further, as illustrated in FIGURES -13, the sections 26 and 28 may be constructed Where the upper section telescopes into the lower section, the clamp structure being accordingly reversed.

The lower laterally extending portions 68 of the Spring latches 60 provide means whereby the pin portion 62 may be dislodged from the aperture 56 and also provides means whereby straps, not shown, may be used to further anchor the frame 22 with respect to the patient P.

Fixedly secured in laterally extending relation from the lower end of the portion `52 of the leg section 28 are foot plates, 70, preferably extending in the direction of the bore `56 for orienting purposes, which may rest on a suitable support surface adjacent the sides of a patient; see FIGURES 10, 12 and 13, to be disposed beneath a patient thereupon or to receive the feet of the operator on the upper surface thereof.

In FIGURES 1 and 2, the foot plates 70 rest on the upper surface of the bed rails 12 and include a suitable transverse apertured portions, the threaded shank 72 of removable J-shaped hold-down elements 74 havingan upwardly turned terminal hook 76 engageable beneath the depending llange of the bed rails 12. A manually manipulable nut 78 is received on the threaded shank 72 and engages the upper surface of the foot plates 70.

It will be apparent that the elements 74 may be readily removed to permit the apparatus to be optionally used in the manner suggested above, to afford versatility of the apparatus, especially during emergency situations in the eld.

The channel element 40 includes an intermediate lateral opening 80 in one side flange 44 and the top web 42 and includes transversely apertured threaded apertures 82 receiving thereover opposed and apertured clamp elements 82 which are retained in position by manually manipulable hold-down screws 84 and include raised lips 86 disposed above the upper surface of the web 42.

Opposite edges of a mounting plate 88 of the force transmitting means 18 are removably received beneath the lips 86 and this expedient facilitates dismantling and portability of the apparatus. The plate 88 has mounted thereon a suitable motor means 90, illustrated in this embodiment as a constant speed, electrically energized motor which can be driven by current from a conventional outlet, battery source, etc. The motor means may comprise an internal combustion engine, fluid pressure driven motor or any suitable force transmitting means. The motor means includes a drive shaft 92 having a polygonally cross-sectioned upper terminal end 94 for accomodating the socket portion 96 of a radially disposed, removable operating handle 98 which comprises emergency, manual operating means in the event of a power failure, etc.

The lower end of the shaft 92; see FIGURES l, 3 and 6, has machined thereon a longitudinally spaced `camming groove or .threaded portion 100 comprising reversely pitched and terminally communicating portions 102 and 104. The shaft will be driven in a single direction and due to the different pitches of the portions 102 and 104, it is possible to attain a different rate of travel of downward and upward movement of the heart manipulating means 20. The degree of pitch of the portions 102 and 104 as indicated in FIGURE 3, is merely illustrative, and as seen in FIGURE 6, shaft 92 may have threaded or camming groove portions 102 and 104 affording the same rate of vertical and reversed travel to a follower element to be described.

The plate 88 has secured thereon in any suitable manner, for example by clamp nuts 106 a depending guide rod 108 having a terminal abutment 110. The heart manipulating means 20 comprises a follower tube 112 telescopically received on the shaft 92 and including in one side an inwardly projecting follower pin 114 which may conveniently comprise an Allen screw, for example, which is received within the threaded or camming groove portion 100. Projecting laterally from an intermediate portion of the follower tube 112 is an arm portion 116 which has a vertically disposed guide sleeve 118 secured thereto and reciprocably received on the guide rod 108; see FIGURE 1.

The shaft 92 is constantly rotated in one direction and the follower sleeve 112 will ascend and descend in a regular rhythm, the motor means 90, being geared down accordingly by any suitable means, and the heart manipulating means will have a downward and upward stroke approximately every second. The groove pitches 102 and 104 may be machined accordingly to obtain the desired rate of travel in either direction, and the follower sleeve 112 is prevented from rotating with the shaft 92 by the guide sleeve 118 and guide rod 108.

The follower sleeve 112 is transversely apertured at its lower end and is received within a transversely apertured Socket portion 120 of a removable and interchangeable pressure-pad element 122. The pressure-pad element may conveniently comprise a metal plate 124 having suitably secured to the underside thereof a resilient pad material 126 of rubber or any other suitable material` The pressure-pad element may come in sets, i.e. several different sizes, to accommodate different sized patients. It Will be noted that the apertures 48 will permit the fOrce transmitting means 18 to be properly positioned slightly to the left of the center of the patients body to obtain the optimum location for the heart manipulating means 20 relative to the heart.

In operation, the frame will -be adjusted to the particular situation, i.e. in the field, bed, etc., the clamp nuts 34 will adjust to the height of the channel 40` and accordingly the maximum descent of the heart manipulating means 20, i.e. to attain approximately l inch of downward and inward movement of the heart manipulating means 20, and the motor means will be operated to attain the rhythmic manipulation and mechanical pumping action of the patients heart. In the event of a power failure, the handle 98 will be available for emergency manual operation of the apparatus.

Another embodiment of force transmitting means 18 is shown in FIGURES 7 and 8, where a channel 240 has mounted thereon a mounting plate 288 having mounted thereon a horizontally disposed motor means 290. The

channel 240 will incorporate legs 24 in opposite ends thereof, of a character similar to those previously described.

The plate 288 includes a depending, angularly disposed bracket 289 which includes an intermediate vertically disposed guide sleeve 291. The bracket 289 projects in the same direction as the motor means drive shaft 292 and has secured thereto a radial lever 293 comprising accentric lever means. The lever is pivotally connected at 294 to a link 295 which is pivotally connected at 296 to a follower rod 212 of heart manipulating means 20. The follower rod 212 is reciprocably received in the sleeve 291 and removably receives on its lower end a pressure pad 122.

In this embodiment a rhythmic, regular upward and downward movement of the heart manipulating means will be attained. This movement or stroke is similar to that attained by the shaft 92 of FIGURE 6.

Considering FIGURE 9, there is disclosed force transmitting means 18 for attaining lan irregular rhythmic stroke similar to that available through the use of the shaft disclosed in FIGURE 3. In this embodiment, the channel 240 has mounted thereon motor means 290 and the mounting plate 288 has a depending bracket 289 including a guide sleeve 291.

The shaft 292 has a cam 293 eccentrically mounted thereon and the periphery 296 thereof is suitably designed and machined to afford different rates of travel of the downward and upward stroke of a heart manipulating means 20".

The heart manipulating means 20 comprises a follower rod 212 having a pressure pad 122 removably secured on the lower end. The rod 212" is reciprocably received in the guide sleeve 291 and has circumposed thereabout a compression spring 297, engaged lat its lower end around sleeve 291 and at its upper end with a transverse abutment pin 298 extending through an intermediate portion of the rod 212". The upper end of the rod 212 is bifurcated and rotatably supports at 299 a cam follower wheel 300 engaged on the peripheral edge 296 of the cam 293. Alternate positions assumed Vby the cam 293 and the spring constantly urges the follower rod 212" upwardly.

Operation of the motor means 290 and cam 293' will cause a rhythmic movement to the heart manipulating means 20" similar to that afforded by the shaft 92 of the embodiment of FIGURES 1-3.

Considering FIGURE 14, a patient P to be treated has mounted about his chest C apparatus 314 which eliminates the rigid frame of the previously Idescribed embodiments.

The apparatus 314 includes a flexible belt 316 of molded rubber or any suitable material which is adjustably mounted by means of snap fasteners 317 or any other suitable means. The belt 316 has formed integrally therewith a suitable housing 318 which will incorporate therein a force transmitting means 18 and heart manipulating means 20.

In this embodiment, the motor means may be battery operated .and the device may be readily positioned at the proper position on the patients chest and operation will be similar to the previously described embodiments.

Considering FIGURES 10 and l1, a hand manipulated embodiment of the apparatus is indicated at 414. The Iapparatus 414 include support means 416, force transmitting means 418 and heart manipulating means 420.

The support means 416 comprises a vertically adjustable legs 424 which include telescoped upper and lower sections 426 and 428, respectively adjustably retained together by a. clamp nut 434. The lower sections 428 include laterally projecting foot plates 470 aud may be rotated inwardly to be anchored beneath the patient in the manner indicated by dotted lines in FIGURE 13.

The upper 'leg sections 426 include at upper ends integral aligned sleeves 427 having ya lock screw 429 extending transversely therethrough. The leg sections 426 include in an intermediate portion thereof vertically extending slots through which extend a support bar 431 including a forwardly projecting, vertically disposed guide sleeve 433.

Received in sleeves 427 are opposite ends of a support rod 435. The lock screws 429 will permit longitudinal adjustment of the legs -a-long the rod 435 to accommodate the apparatus to different width patients and to permit proper positioning of the heart manipulating means 420. The legs are vertically adjustable by virtue of the clamp nuts 434 to adjust to the chest height of a patient and pressure to be applied to the patients chest.

Depending from an intermediate portion of the rod 435 are support straps 437 having a horizontal shaft 439 upon which is mounted a vertically pivotal, hand manipulatable lever 441 which is oriented by spacer elements 443. The lever 441 includes a rear handle 445 and forward, longitudinal lost motion slot 447. Connected by a transverse pin 449 extending through a bifurc-ated portion 451 and the slot 447 is a vertically disposed rod 453 reciprocably received in the guide sleeve 443. Removably secured at the lower end of the rod is a pressure pad 122.

Vertical reciprocation of the lever 441 will control the stroke of the rod 453. To prevent excessive downward pressure of the heart manipulating means 420, there is a rearwardly projecting portion 45S supporting a vertically adjustable abutment screw 457 which is in alignment with and engageable by the lever 441.

Referring to FIGURES 12 and 13, there is shown another manually operated embodiment 414 of the apparatus. This embodiment includes support means 416', force transmitting means 418 and heart manipulating means 420.

The frame of this embodiment will overly the patient and includes vertically adjustable legs 424 including a lower leg portion 428 including a lower foot plate 470. The foot plates 470 may be rotated beneath a patient as indicated by dotted lines in FIGURE 13, and the leg sections support therein upper leg sections 426 retained in vertically adjusted relation in sections 428 by clamp nuts 434.

The leg sections have secured thereto a transverse support plate 435 from which projects a vertically disposed sleeve 433. Reciprocably received in the sleeve 433 is a rod 453 having formed at the upper end an integral gear rack portion 447. The lower end of the rod 435 has removably secured thereto a pressure pad 122.

Mounted between a pair of vertically extending plates 437 cammed on a forward face of the plate 435 is a pin 439 upon which is intermediately pivoted a lever 441 including a handle 445. The forward end of the lever 441 has an integral gear segment 448 meshing with the gear rack 447.

Reciprocation of the lever 441 will control the pressure and duration of the stroke of the heart manipulating means 420', however, excess pressure or stroke is prevented by a rearwardly projecting plate 455 supporting a vertically adjustable abutment screw 457 in alignment with the path of travel of the lever 441'.

Thus there has 'been disclosed various embodiments of the novel apparatus which fully conforms with the objects of the invention.

While there has been illustrated preferred embodiments of the invention, modifications will occur to those skilled in the art without departing from the spirit of the invention, and thus I do not intend to limit the invention to what is shown and described in detail, but desire to avail myself of all changes and modifications within the scope of the appended claims.

What is claimed as new is as follows:

1. Apparatus for reactivating the heart of a human patient following cessationof heart beat, comprising a support underlying the back of said patient inclusive of the cardiac region, a resilient pressure applicator including a rigid plate and a resilient pressure pad secured to the underside of said rigid plate, said plate and pressure pad having an area only sucient to substantially cover the human breastbone, means for positioning said pressure pad in a position exteriorly of the body of the patient and substantially over the breastbone of the patient and in Contact with the body of the patient, said means including a reciprocable substantially vertical shaft having said pressure applicator secured to its lower end, adjustable means for locating and maintaining said shaft and said applicator in position with said pressure pad in contact with said patient and directly overlying said breastbone, power means imparting rhythmical downward followed by upward motions to said shaft at a rate approximately equal to the normal rate of heart beat and with strokes and pressures sufficient to compress said breastbone only to the minimum extent required to effect perfusion in the heart followed by substantially complete releases of said breastbone from the pressure of said pad, and means providing a force reaction between said pad and said support, whereby the breastbone may be depressed repetitively by the same amount over a long time period while said back is retained substantially immovable with respect to the lowermost position of'said pad during said rhythmical motions of said shaft, wherein said power means includes an electric motor, a cam actuated periodically by said electric motor, said cam being in driving relation to said shaft, wherein is provided spring means alone retaining said shaft in actuable relation with respect to said cam, and wherein said cam is designed to provide a relatively rapid depression and relatively slower rise of said pressure pad.

2. Apparatus for reactivating the heart of a human patient comprising a pressure applicator, means cornprising at least one flexible belt for securing said applicator to the chest of said patient, said applicator including an elongated cylindrical housing, a motor means contained in said housing, a shaft largely extending within said housing parallel to the axis thereof, said shaft having a further end terminating in a resilient pressure pad having a shape and area adapted to substantially cover only the sternum of said human patient, means responsive to said motor means for reciprocating said pressure pad, means securing said flexible belt to said housing at least at opposed points thereof located near the end of said housing located adjacent said pressure pad, and means for adjusting said flexible belt to hold said pressure pad against said sternum and said housing substantially perpendicular to said sternum when said shaft is in its innermost location in said housing, said motor means being arranged and adapted to impart rhythmical downward followed by `upward motions of said shaft at a rate approximately equal to the normal rate of heart beat and with strokes and pressures suflicient to effect perfusion in the heart followed by substantially complete releases of said breastbone from the pressure of said pad.

3. Apparatus for reactivating the heart of a human patient following cessation of heartbeat, comprising a pressure applicator including a resilient pressure pad, said pressure pad having an area sucient to substantially cover the human Ibreastbone, means comprising a belt device extending about said patient for maintaining said pressure pad externally of the body of the patient and over the breastbone of the patient and in contact with the body of the patient and for providing a force reaction holding said patient immovable against said pressure pad during movements thereof, power means including a reciprocable substantially vertical shaft having said pressure applicator secured to its lower end operative for imparting rhythmical downward followed by upward motions to said pressure pad at a rate approximately equal to the normal rate of heart beat and with strokes and pressures sufficient to compress said breastbone only to the minimum extent required to effect perfusion in the heart followed by substantially complete releases of said breastbone from the pressure of said pad, and means securing said belt device to said power means, whereby the breastbone may be depressed repetitively in response to operation of said power device in a fixed movement over a long period of time.

4. The combination according to claim 3 wherein said power means includes an external cylindrical housing for said shaft, said housing extending substantially vertically of said patient, a motor located internally of said housing, said belt being fixedly secured to said housing at least adjacent the portion of said housing located nearest said patient, said shaft and applicator being movable with respect to said housing by said motor.

References Cited UNITED STATES PATENTS 1,918,546 7/1933 Johnson 12S- 28 2,062,300 12/1936` Erickson 12S-52 X 2,484,306 10/1949 McClain 12S-28 FOREIGN PATENTS 33,302 6/ 1908 Australia.

OTHER REFERENCES Boehm, R. V. Arbeiten aus dem sharmakol ogischen Institute der Universitat Dorpat, 13; Ubr Weiderbelebung nach Vergiftungen und Asphyxie, Arch. Exper. Path. U. Pharmalcol. 8, 68-1011, 1878.

Kouwenhoven, W. B., Jude, Jr. Knickerbocker G. G.: Closed Chest Cardiac Massage, J.A.M.A. 173, 1064-1067 July 9, 1960.

L. W. TRAPP, Primary Examiner 

1. APPARATUS FOR REACTIVATING THE HEART OF A HUMAN PATIENT FOLLOWING CESSATION OF HEART BEAT, COMPRISING A SUPPORT UNDERLYING THE BACK OF SAID PATIENT INCLUSIVE OF THE CARDIAC REGION, A RESILIENT PRESSURE APPLICATOR INCLUDING A RIGID PLATE AND A RESILIENT PRESSURE PAD SECURED TO THE UNDERSIDE OF SAID RIGID PLATE, SAID PLATE AND PRESSURE PAD HAVING AN AREA ONLY SUFFICIENT TO SUBSTANTIALLY COVER THE HUMAN BREASTBONE, MEANS FOR POSITIONING SAID PRESSURE PAD IN A POSITION EXTERIORLY OF THE BODY OF THE PATIENT AND SUBSTANTIALLY OVER THE BREASTBONE OF THE PATIENT AND IN CONTACT WITH THE BODY OF THE PATIENT, SAID MEANS INCLUDING A RECIPROCABLE SUBSTANTIALLY VERTICAL SHAFT HAVING SAID PRESSURE APPLICATOR SECURED TO ITS LOWER END, ADJUSTABLE MEANS FOR LOCATING AND MAINTAINING SAID SHAFT AND SAID APPLICATOR IN POSITION WITH SAID PRESSURE PAD IN CONTACT WITH SAID PATIENT AND DIRECTLY OVERLYING SAID BREASTBONE, POWER MEANS IMPARTING RHYTHMICAL DOWNWARD FOLLOWED BY UPWARD MOTIONS TO SAID SHAFT AT A RATE APPROXIMATELY EQUAL TO THE NORMAL RATE OF HEART BEAT AND WITH STROKES AND PRESSURES SUFFICIENT TO COMPRESS SAID BREASTBONE ONLY TO THE MINIMUM EXTENT REQUIRED TO EFFECT PERFUSION IN THE HEART FOLLOWED BY SUBSTANTIALLY COMPLETE RELEASES OF SAID BREASTBONE FROM THE PRESURE OF SAID PAD, AND MEANS PROVIDING A FORCE REACTION BETWEEN SAID PAD AND SAID SUPPORT, WHEREBY THE BREASTBONE MAY BE DEPRESSED REPETITIVELY BY THE SAME AMOUNT OVER A LONG TIME PERIOD WHILE SAID BACK IS RETAINED SUBSTANTIALLY IMMOVEABLE WITH RESPECT TO THE LOWERMOST POSITION OF SAID PAD DURING SAID RHYTHMICAL MOTIONS OF SAID SHAFT, WHEREIN SAID POWER MEANS INCLUDES AN ELECTRIC MOTOR, A CAM ACTUATED PERIODICALLY BY SAID ELECTRIC MOTOR, SAID CAM BEING IN DRIVING RELATION TO SAID SHAFT, WHEREIN IS PROVIDED SPRING MEANS ALONE RETAINING SAID SHAFT IN ACTUABLE RELATION WITH RESPECT TO SAID CAM, AND WHEREIN SAID CAM IS DESIGNED TO PROVIDE A RELATIVELY RAPID DEPRESSION AND RELATIVELY SLOWER RISE OF SAID PRESSURE PAD. 